OAKLAND — The A’s are not ready to commit to Scott Sizemore as their second baseman.

Manager Bob Melvin said Sunday at FanFest that Sizemore, who was a third baseman at this time a year ago but who got hurt in spring training and missed the season, has many plusses.

“As a Major League baseball player, you have to look at it every day that this is my job; you have to fight all the time,” Melvin said. “So it’s Sizemore, Adam Rosales and I expect Jemile Weeks to come back and play to his ability. And just because a guy starts on opening day doesn’t mean that (someone else) won’t be in the lineup the next day based on matchups. We’ll look to keep everybody part of it.”

Weeks, the starter a year ago after a strong rookie season, fell off so badly that he was sent back to the minors at one point.

Melvin expects better this time around.

“It’s not uncommon for a guy to have a great rookie season, then take a step back,” Melvin said. “His talent level has not gone away, no distractions will get in the way. We’ve seen what he can do. The opportunity is still there for him.”